Flame retardant composition process for producing the same, flame-retardant resin composition, and molded object thereof

ABSTRACT

A molded article is produced from a flame retardant resin composition obtained by compounding a thermoplastic resin or thermosetting resin with a flame retardant composition comprising as essential ingredients a fluorine compound (A) represented by the following formula (1): 
 
R 1 —SO 2 —R 2  or R 1 —SO 3   − M +   (1) 
 
(wherein R 1  represents a C 1 -C 12  perfluoroalkyl group, a C 2 -C 8  perfluoroalkenyl group, a C 6 -C 12  perfluoroaryl group which may be substituted, a C 3 -C 12  perfluoroalicyclic hydrocarbon group, or a C 7 -C 12  perfluoroaralkyl group; R 2  represents a halogen atom, an N-alkylamino group, or an N-alkyl-N-hydroxyalkylamino group; and M represents an alkali metal) and a polyester resin (B). The molded article has flame retardancy despite addition of the fluorine compound (A) in a very small amount. Excellent dispersion of the fluorine compound (A) is attained, and bleeding of the compound (A) is prevented.

TECHNICAL FIELD

The present invention relates to a novel flame retardant composition, toa process for producing the composition, to a flame retardant resincomposition, and to a molded article of the resin composition. Moreparticularly, the present invention relates to a flame retardantcomposition containing a fluorine compound which exerts excellent flameretardant effect, despite being present in a considerably small content,and a polyester resin which has excellent compatibility with a varietyof resins and solubility in solvent; to a process for producing thecomposition; and to a flame retardant resin composition and a moldedarticle produced from the resin composition in which bleeding of theflame retardant is suppressed.

BACKGROUND ART

Thermoplastic resins (e.g., polypropylene resin, polystyrene resin, ABSresin, polycarbonate resin, and polyester resin) and thermosettingresins (e.g., epoxy resin, polyurethane resin, and phenolic resin) haveexcellent characteristics such as the ability to be produced atcomparatively low cost, and easy moldability. Therefore, these resinsfind a wide range of uses such as electronic materials and automobileparts.

These resins are generally highly flammable. Thus, such a thermoplasticresin requires, for use thereof, flame-retarding treatment; i.e., addinga flame retardant and a flame retardant auxiliary to the resin. Inrecent years, higher performance (flame retardancy, mechanicalcharacteristics, heat resistance, electrical insulating property, etc.)of thermoplastic resins has been required as the type of use of theresins diversifies and the scale of the resin products increases.

As disclosed in Japanese Patent Application Laid-Open (kokai) No.11-343382, flame retardancy is generally imparted to thermoplastic resinthrough a method including adding a halogen-containing flame retardantto a resin composition upon preparation thereof. However, such ahalogen-containing flame retardant, which effectively imparts flameretardancy to resin, generates hydrogen halide as a result of thermaldecomposition thereof during molding of the resin at high temperature,and the thus-generated hydrogen halide may corrode metallic portions ofa mold, a molding machine, an apparatus relating to molding, orelectronic/electric parts.

As halogen-free flame retardants, inorganic metallic compounds such asmagnesium hydroxide, aluminum hydroxide, calcium hydroxide, and basicmagnesium carbonate are employed. Among them, magnesium hydroxide iswidely used, by virtue of its high dehydration-decomposition temperatureand excellent smoke suppression effect during flaming. However, in orderto attain sufficient flame retardant effect, magnesium hydroxide must beadded in a large amount, which results in a considerable drop inintrinsic physical properties of resin, particularly mechanicalcharacteristics.

As halogen-free flame retardants other than inorganic metalliccompounds, organic phosphorus compounds are also generally employed.Examples of generally known such organic phosphorus compounds includelow-molecule phosphate esters such as trimethyl phosphate and triphenylphosphate. For example, Japanese Patent Application Laid-Open (kokai)No. 61-291644 discloses that an ABS resin can be imparted with flameretardancy by adding a resol-type phenolic resin and red phosphorus tothe ABS resin. Japanese Patent Application Laid-Open (kokai) Nos.6-248160 and 7-48491 disclose that techniques for imparting flameretardancy to an ABS resin in which a phenolic resin and an organicphosphorus compound are added to the ABS resin without deterioratingimpact resistance of the resin. However, although the resinscompositions disclosed in the above publications have excellent flameretardancy and mechanical characteristics, heat resistance of thecompositions is unsatisfactory. Particularly, the compositions aredifficult to use as members which require high heat resistance (i.e.,parts employed in portions which are locally heated; e.g., automobileengine-related parts and heat-transfer rollers in copying machines).

The organic phosphorus compounds have another drawback. Namely, sincethe phosphorus compounds impart a resin with plasticity as well as flameretardancy, heat deformation temperature and softening temperature ofthe resin drop considerably. Flame retardant ABS resin compositions areknown to be deteriorated in terms of electric characteristics and flameretardancy due to absorption of water to the resin compositions, whenthe resin compositions are used under severe (high temperature andmoisture) conditions as a variety of electric/electronic parts (e.g.,television set parts and personal computer parts) or automobile parts.

The most critical drawback of these halogen-containing or halogen-freeflame retardants is that the flame retardants bleed from the resin dueto their poor dispersibility in the resin during storage of the flameretardant resin composition at high temperature for a long time, therebyimpairing appearance of resin products. In addition, when a flameretardant bleeds out to the surface of the resin article, the flameretardant is adsorbed on the human body during handling of the article,which is problematic in view of safety. In order to solve theseproblems, a variety of countermeasures have been proposed; for example,a method in which a specific compound is added to polyolefin resin(Japanese Patent Application Laid-Open (kokai) No. 6-299007); and amethod in which an inorganic filler is added to crystalline propylenepolymer to which a halogen-containing flame retardant and a flameretardant aid have been added (Japanese Patent Application Laid-Open(kokai) No. 7-53796). However, currently, these two methods do notprovide satisfactory effect on suppressing bleeding of a flameretardant. In order to solve the problem, Japanese Patent ApplicationLaid-Open (kokai) No. 2000-154282 discloses a method in which ahalogen-containing flame retardant and a polyester resin areincorporated into a polyolefin resin, thereby suppressing bleeding ofthe flame retardant. However, the above effect can be attainedsatisfactorily only when the halogen-containing flame retardant is addedin a large amount to the polyester resin. Thus, the intrinsiccharacteristics of the resin to which the flame retardant is added areimpaired, which is problematic.

Meanwhile, the fluorine compound (A) used in the present invention canimpart very effective flame retardancy to a resin through addition ofthe compound (A) in a trivial to very small amount of some ppm to some%. However, similar to the case of other flame retardants, the compound(A) also has the problem of poor dispersibility in resin. In order toimpart excellent flame retardancy to a resin, a uniform dispersion stateof a flame retardant is essential, and therefore, in some cases theresin must be kneaded several times at high temperature. Such kneadingmay cause decomposition of resin and may rather deteriorate flameretardant properties of the resin concomitant with drip generation.

DISCLOSURE OF THE INVENTION

An object of the present invention for solving the aforementionedproblems is to provide an excellent flame retardant composition whichexhibits good dispersibility in a variety of resins, prevents bleedingof a flame retardant, and can provide flame retardant effect throughaddition of the composition in a small amount, thereby not deterioratingphysical properties of the resins. Another object of the invention is toprovide a process for producing the flame retardant composition.

Still another object of the invention is to provide a flame retardantresin composition to which the flame retardant composition has beenadded and which has a halogen content in the resin as small as possible,thereby reducing the impact of the composition upon the environmentduring discharge and firing of the resin. Yet another object of theinvention is to provide a molded article having flame retardancy formedby molding the flame retardant resin composition.

The present inventors have carried out extensive studies in order tosolve the aforementioned problems, and have found that, throughco-presence of a polyester resin, a specific fluorine compound can bereadily added to a variety of resins with high dispersibility, therebypreventing bleeding of a flame retardant, and can impart flameretardancy to resin through addition of the compound in a very smallamount.

The present inventors have also found that a flame retardant compositioncan be produced more easily by polymerizing a lactone monomer in thepresence of a fluorine compound (A).

Furthermore, the present inventors have also found that a flameretardant composition can be produced easily by preliminary mixing thefluorine compound and the polyester resin, and that a flame retardantresin composition which exhibits flame retardancy without impairing theintrinsic properties of the resin can be produced by blending a smallamount of the flame retardant composition with a thermoplastic resin ora thermosetting resin, and a molded article can be produced by moldingthe resin composition.

Accordingly, the present invention provides a flame retardantcomposition, characterized in that the composition comprises, asessential ingredients, a fluorine compound (A) represented by thefollowing formula (1):R¹—SO₂—R² or R¹—SO₃ ⁻M⁺  (1)(wherein R¹ represents a C₁-C₁₂ perfluoroalkyl group, a C₂-C₈perfluoroalkenyl group, a C₆-C₁₂ perfluoroaryl group which may besubstituted, a C₃-C₁₂ perfluoroalicyclic hydrocarbon group, or a C₇-C₁₂perfluoroaralkyl group; R² represents a halogen atom, an N-alkylaminogroup, or an N-alkyl-N-hydroxyalkylamino group; and M represents analkali metal) and a polyester resin (B).

The present invention also provides a process for producing a flameretardant composition, characterized in that the process comprisespolymerizing a lactone monomer in the presence of a fluorine compound(A) represented by the following formula (1):R¹—SO₂—R² or R¹—SO₃ ⁻M⁺  (1)(wherein R¹ represents a C₂-C₁₂ perfluoroalkyl group, a C₂-C₈perfluoroalkenyl group, a C₆-C₁₂ perfluoroaryl group which may. besubstituted, a C₃-C₁₂ perfluoroalicyclic hydrocarbon group, or a C₇-C₁₂perfluoroaralkyl group; R² represents a halogen atom, an N-alkylaminogroup, or an N-alkyl-N-hydroxyalkylamino group; and M represents analkali metal). The invention also provides a flame retardant resincomposition formed of the aforementioned flame retardant composition anda thermoplastic or thermosetting resin, as well as a molded articleformed by molding the aforementioned flame retardant resin composition.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will next be described in detail.

The flame retardant composition of the present invention contains asessential ingredients a fluorine compound represented by theaforementioned formula (1) (A) and a polyester resin (B).

Firstly, the fluorine compound serving as the ingredient (A) used in thepresent invention will be described.

Among a variety of species of R¹ in formula (1) , the C₁-C₁₂perfluoroalkyl group may be a linear chain or branched chain alkylgroup. Specific examples of corresponding C₁-C₁₂ alkyl groups includelinear chain alkyl groups such as methyl, ethyl, n-propyl, n-butyl,n-pentyl, n-hexyl, n-heptyl, and n-octyl; and branched chain alkylgroups such as isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl,tert-pentyl, neopentyl, isohexyl, methylhexyl, methylheptyl,dimethylhexyl, and 2-ethylhexyl. Of these, lower alkyl groups such asmethyl, ethyl, n-propyl, n-butyl, isopropyl, isobutyl, sec-butyl, andtert-butyl are preferred, with methyl and ethyl being particularlypreferred.

Examples of the C₂-C₈ alkenyl group of such C₂-C₈ perfluoroalkenylgroups include vinyl, allyl, isopropenyl, butenyl, pentenyl, hexenyl,heptenyl, and octenyl. Of these, allyl is particularly preferred.

Examples of the optionally substituted C₆-C₁₂ aryl groups correspondingto C₆-C₁₂ perfluoroaryl groups which may be substituted include phenyl,(o-, m-, p-)cresyl, (o-, m-, p-)tolyl, (2,3-, 2,4-, 2,5-, 2,6-, 3,4-,3,5-)xylyl, mesityl, trimethylphenyl, ethylphenyl, propylphenyl,butylphenyl, nitrophenyl, methoxyphenyl, and naphthyl. Of these, phenyl,cresyl, and xylyl are particularly preferred.

Examples of the C₃-C₁₂ alicyclic hydrocarbon group of such C₃-C₁₂perfluoroalicyclic hydrocarbon groups include saturated alicyclichydrocarbon groups and unsaturated alicyclic hydrocarbon groups, withsaturated alicyclic hydrocarbon groups being preferred. Examples ofpreferred saturated alicyclic hydrocarbon groups include cyclopentyl,cyclohexyl, and cycloheptyl. Of these, cyclohexyl is particularlypreferred.

Examples of preferred C₇-C₁₂ aralkyl groups of such C₇-C₁₂perfluoroaralkyl groups include benzyl and phenethyl. Of these, benzylis particularly preferred.

Among a variety of species of R² in formula (1), the halogen atom isfluorine, chlorine, or bromine. The alkyl group constituting theN-alklyamino group or the N-alkyl-N-hydroxyalkylamino group is a C₁-C₄alkyl group, preferably methyl, ethyl, or propyl.

M in formula (1) represents an alkali metal including lithium, sodium,and potassium.

Examples of preferred fluorine compounds represented by formula (1)include potassium perfluorobutylsulfonate, potassiumperfluorooctylsulfonate, lithium perfluorooctylsulfonate, potassiumperfluoro-4-ethylcyclohexylsulfonate, perfluorobutanesulfonyl fluoride,perfluorohexanesulfonyl fluoride, perfluorooctanesulfonyl fluoride,N-ethylperfluorooctanesulfonamide, andN-ethyl-N-hydroxyethylperfluorooctanesulfonamide. Of these, potassiumperfulorobutylsulfonate is preferably used.

These compounds may be used singly or in combination.

Example of the polyester resin serving as the ingredient (B) used in thepresent invention include lactone polymers obtained through ring-openingpolymerization of a C₄-C₁₁ lactone; polyester resins obtained throughcondensation between an aliphatic dicarboxylic acid (e.g., oxalic acid,succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid,azelaic acid, sebacic acid, or dodecanedioic acid) or an aromaticdicarboxylic acid (e.g., terephthalic acid, isophthalic acid, oro-phthalic acid) and an aliphatic diol (e.g., ethylene glycol,1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol,3-methyl-1,5-pentanediol, 1,6-hexanediol, or 1,9-nonanediol), analicyclic diol (e.g., cyclohexane-1,4-dimethanol), or an ether diol(e.g., tetramethylene glycol); lactone-modified polyester resinsobtained through copolymerization of a polyester resin and a lactone;resins of an aliphatic or aromatic hydroxycarboxylic acid polymer;hydroxycarboxylic acid (e.g., 3-hydroxybutylate and 3-hydroxyvalerate)copolymer resins; and mixtures thereof.

These aliphatic dicarboxylic acids and aromatic dicarboxylic acids maybe used in combination of two or more species. Also, these diols may beused in combination of two or more species.

The aliphatic or aromatic polyester resin serving as the aforementionedingredient (B) can be produced through a known method. For example, thepolyester resin can be produced through a method includingtransesterification between a lower alcohol ester of a dicarboxylic acidand an excessive amount of a glycol in the presence of a catalyst,followed by polycondensation of the formed reaction product.Alternatively, the polyester resin can also be produced through a methodincluding esterification of a dicarboxylic acid with an excessive amountof a glycol in the presence of a catalyst, followed by polycondensationof the formed reaction produced.

The reaction temperature is 180 to 290° C., preferably 200 to 280° C.

Examples of polycondensation catalysts include titanium compounds,antimony compounds, tin compounds, calcium compounds, and manganesecompounds. Any of these catalysts is used in an amount of 0.1 to 1,000ppm based on the weight of the starting material, preferably 0.5 to 500ppm.

Among the polyester resins, lactone polymers are preferred. Examples ofthe monomers for producing lactone polymers include ε-caprolactone,trimethyl-ε-caprolactone, monomethyl-ε-caprolactone, γ-butyrolactone,and δ-valerolactone. These monomers may be used singly or in combinationof two or more species, and may be co-polymerized. Among the lactonepolymers, poly(ε-caprolactone) is preferably used from the viewpoints ofcompatibility with resin and dispersibility of the fluorine compound (A)therein.

According to the present invention, when a lactone polymer is employedas the polyester (B), the flame retardant composition can readily beproduced through polymerization of a lactone monomer in the presence ofthe fluorine compound (A).

The method for polymerizing a lactone monomer includes mixing thelactone monomer and a polymerization initiator and stirring the mixturefor several hours preferably in the presence of a catalyst at 120° C. to230° C., preferably at 140° C. to 220° C., in a continuous or batchreaction manner. The polymerization initiator used herein is a compoundhaving one or more active hydrogen atoms; i.e., water and hydroxylgroups.

Examples of compounds having hydroxyl groups include alkylene glycolssuch as ethylene glycol, propylene glycol, 1,4-butanediol, 2,3-butyleneglycol, pentamethylene glycol, hexamethylene glycol, glycerin,trimethylolpropane, ditrimethylolpropane, pentaerythritol, anddipentaerythritol.

As the polymerization catalyst, a variety of organic and inorganicmetallic compounds may be used. Specific examples include organictitanium compounds such as tetrabutyl titanate, tetraisopropyl titanate,and tetraethyl titanate; organic tin compounds such as dibutyltin oxide,dibutyltin laurate, stannous octylate, and mono-n-butyltin fatty acidsalts; and stannous halides such as stannous chloride, stannousbromide., and stannous iodide. Any of these catalyst is used in anamount of 0.1 ppm to 1,000 ppm based on the weight of the startingmaterial, preferably 0.5 ppm to 500 ppm.

The polyester resin (B) used in the present invention has a numberaverage molecular weight of 1,000 to 500,000, preferably 5,000 to200,000, more preferably 10,000 to 100,000.

When the number average molecular weight is less than 1,000, bleedingprevention effect cannot be attained. On the other hand, when themolecular weight is in excess of 500,000, the polyester cannot bemelt-kneaded with a variety of resins. The number average molecularweight employed herein is determined through gel permeationchromatography.

In the present invention, when the flame retardant composition isproduced from the fluorine compound (A) and the polyester (B) throughthe aforementioned method (i.e., only melt-mixing), the ingredients maybe kneaded by means of a kneader such as a single screw extruder, a twinscrew extruder, a Banbury mixer, or a kneader mixer. No particularlimitation is imposed on the order of blending the ingredients andmixing method for the ingredients.

The ratio of the fluorine compound (A) to the polyester resin (B)contained in the flame retardant composition may be determinedappropriately in accordance with the type of the thermoplastic resin orthermosetting resin to be blended with the composition. Generally, theratio by weight of (A)/(B) is (0.1 to 90)/(99.9 to 10), preferably (20to 80)/(80 to 20). When the ratio is less than 0.1/99.9, the effect ofthe ingredient (A) cannot be attained. On the other hand, when the ratiois in excess of 90/10, the fluorine compound (A) may bleed out from aflame retardant resin composition obtained by blending the flameretardant composition with a thermoplastic resin or thermosetting resinor a molded article obtained by molding the resin composition. The abovetwo cases are not preferred.

By adding the flame retardant composition of the present invention to athermoplastic resin or thermosetting resin, the flame retardant resincomposition and the molded product of the resin composition can beproduced.

Specific examples of the thermoplastic resin include polyethylene resin,chlorinated polyethylene resin, polypropylene resin, polybutadieneresin, polymethylpentene resin, poly(butene-1) resin, polystyrene resin,impact-resistant polystyrene resin, poly((meth)acryl-styrene) resin,poly(phenylene ether) resin, poly(phenylene sulfide) resin,poly(phenylene oxide) resin, modified poly(phenylene oxide) resin,polyacrylonitrile resin, polyamide (nylon) resin, poly(ethyleneterephthalate) resin, poly(butylene terephthalate) resin, polycarbonateresin, polyvinyl alcohol resin, polyvinyl acetal resin, polyacetalresin, polysulfone resin, polyester resin, hydroxybenzoic acid polyesterresin, poly(vinyl chloride) resin, poly(vinyl bromide) resin, poly(vinylfluoride) resin, poly(vinyl acetate) resin, poly(vinylidene chloride)resin, acrylonitrile-styrene (AS) resin, acrylonitrile-butadiene-styrene(ABS) resin, acrylonitrile-chlorinated polyethylene-styrene (ACS) resin,fluororesin, (meth)acrylic resins such as poly(methyl (meth)acrylate)resin, polycarbonate-ABS resin (resin alloy), vinyl chloride-styrenecopolymer, vinyl chloride-ethylene copolymer, vinyl chloride-propylenecopolymer, vinyl chloride-isobutylene copolymer, vinylchloride-vinylidene chloride copolymer, vinyl chloride-chlorinatedpropylene copolymer, vinyl chloride-butadiene copolymer, vinylchloride-isoprene copolymer, styrene-butadiene copolymer,acrylonitrile-butadiene copolymer, ethylene-vinyl acetate copolymer,ethylene-propylene copolymer, vinyl chloride-vinyl acetate copolymer,vinyl chloride-ethylene-vinyl acetate terpolymer, vinylchloride-styrene-maleic anhydride terpolymer, vinylchloride-styrene-acrylonitrile terpolymer, vinyl chloride-vinylidenechloride-vinyl acetate terpolymer, vinyl chloride-(meth)acrylic acidester copolymer, vinyl chloride-maleic acid ester copolymer, vinylchloride-acrylonitrile copolymer, and (meth)acrylic acidester-butadiene-styrene copolymer.

Among the above-exemplified resins and polymers, polyethylene resin,chlorinated polyethylene resin, polypropylene resin, polybutadieneresin, polystyrene resin, impact-resistant polystyrene resin,poly(methyl methacrylate) resin, poly(phenylene oxide) resin, modifiedpoly(phenylene oxide) resin, polyamide resin, polycarbonate resin,polyester resin, poly(vinyl chloride) resin, AS resin, ABS resin, andACS resin are preferred, since dripping resistance can be envisaged.

Examples of the thermosetting resin include polyurethane resin, phenolicresin, melamine resin, urea resin, epoxy resin, silicone resin, diallylphthalate resin, polyimide resin, and unsaturated polyester resin. Amongthe above-exemplified resins, polyurethane resin, phenolic resin,melamine resin, urea resin, epoxy resin, and unsaturated polyester resinare particularly preferred.

The flame retardant composition formed of the fluorine compound (A) andthe polyester resin (B) and the thermoplastic resin or thermosettingresin can be melted and kneaded together by means of an apparatus suchas a single screw extruder, a twin screw extruder, a Banbury mixer, or akneader mixer. No particular limitation is imposed on the order ofblending the ingredients and mixing method for the ingredients. Notably,the flame retardant resin composition of the present invention can alsobe produced by mixing three ingredients: the fluorine compound (A), thepolyester resin (B), and the thermoplastic resin or thermosetting resin.

By virtue of the presence of the polyester resin (B), which is onecharacteristic feature of the present invention, the fluorine compound(A) can be uniformly micro-dispersed in resin.

The amount (flame retardancy effective amount) of the flame retardantcomposition added to the flame retardant resin composition of thepresent invention may be appropriately determined in accordance with thetype of the resin used, use of the resin, and demanded performance ofthe resin.

The fluorine compound (A) serving as a flame retardant used in thepresent invention provides remarkable flame retardancy despite additionthereof in a small amount. The amount of the fluorine compound (A) inthe flame retardant resin composition falls within a range of 0.001% byweight to 10% by weight, preferably 0.005% by weight to 5% by weight,more preferably within a range of 0.1% by weight to 1% by weight orthereabouts.

When the amount of the fluorine compound (A) in the flame retardantresin composition is less than 0.001% by weight, flame retardant effectcannot be attained. On the other hand, when the compound (A) is used inan amount more than 10% by weight, flame retardant effect commensuratewith the addition cannot be attained, resulting in increase in cost andimpairment of intrinsic characteristics of the resin. The two cases arenot preferred.

The polyester resin (B) used in the present invention is contained inthe flame retardant resin composition in an amount falling within arange of 0.1% by weight to 10% by weight, preferably within a range of0.1% by weight to 1% by weight or thereabouts. When the amount of thepolyester resin (B) in the flame retardant resin composition is lessthan 0.1% by weight, compatibility of the polyester resin with thefluorine compound (A) serving as a flame retardant may be adverselyaffected. On the other hand, when the polyester resin is used in anamount more than 10% by weight, intrinsic characteristics of the resinwhich differs from polyester and is incorporated into the resincomposition are adversely affected. The two cases are not preferred.

The flame retardant composition or the flame retardant resin compositionof the present invention may contain, in accordance with needs, anadditional flame retardant and one or more additives such as anantioxidant, a filler, a stabilizer, a colorant, an antistatic agent, alubricant, a nucleating agent, and an anti-blooming agent.

Examples of the flame retardant other than the compound (A) includehalogen-free phosphate ester compounds, halogen-containing phosphateester compounds, inorganic compounds, nitrogen-containing compounds, andammonium phosphate salts.

Examples of halogen-containing phosphate ester compounds includetris(β-chloroethyl) phosphate, tris(2,3-dibromopropyl) phosphate,tris(tribromoneopentyl) phosphate, bis(chloroethyl)(tribromoneopentyl)phosphate, diethylene glycol bis(β-chloropropyl) phosphate, anddiethylene glycol bis(β-chloroethyl) phosphate. There may also beemployed halogen compounds such as tetrabromoethane andhexabromocyclodecane; phosphate ester compounds having a phosphorinaneskeleton or a bicyclo skeleton such as phosphonate ester compounds(e.g., 2-ethylhexyl mono-2-ethylhexylphosphonate and 2-ethylhexyldi-2-ethylhexylphosphonate); organic phosphine oxide compounds; andhalogenated organic phosphine oxide compounds.

Examples of the inorganic compounds include magnesium hydroxide,aluminum hydroxide, and antimony trioxide. Particularly when the resinis modified poly(phenylene oxide) resin, polystyrene resin, or ABSresin, the fluorine compound of the present invention is preferably usedin combination with any of the aforementioned inorganic compounds.

Examples of the antioxidant include phosphorus compounds, hydroquinonecompounds, phenol compounds, amine compounds, and sulfur compounds. Ofthese, hydroquinone compounds and phosphorus compounds are preferred.These antioxidants may be used singly or in combination of two or morespecies. Through addition of any of these antioxidants, a flameretardant resin composition having excellent heat resistance and foggingproperties can be produced.

Specific examples of the hydroquinone compounds include hydroquinone,2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, andoctylhydroquinone. Of these, 2,5-di-tert-amylhydroquinone isparticularly preferred from the viewpoint of enhancement of heatresistance of the flame retardant resin composition.

Specific examples of the phosphorus compounds include trivalent organicphosphorus compounds such as triphenyl phosphite, tris(nonylphenyl)phosphite, diphenyl(isodecyl) phosphite,bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, andtetrakis(2,4-di-tert-butylphenyl)-4,4-diphenylene phosphonite.

Examples of the filler include silica, talc, graphite, carbon black,titanium oxide, and alumina.

The flame retardant resin composition of the present invention can beproduced by adding a flame retardant composition containing the fluorinecompound (A) and the polyester resin (B) to a monomer supplied forproducing the resin at bulk polymerization (1); to a bulk polymerizationmixture at a final reaction stage for producing the resin (2); or to theresin during kneading (3).

By molding the flame retardant resin composition through a known method,flame retardant molded articles of a desired shape such as plate, sheet,or film can be obtained. The thus-obtained molded articles haveexcellent flame retardancy, heat resistance, and electrical insulationproperty as well as excellent mechanical properties, and have favorableappearance.

Examples of the aforementioned molded articles obtained from the flameretardant resin composition of the present invention include householdelectric appliances such as refrigerator back covers, washing machinecapacitor covers, television set back covers, television set speakerboxes, deflecting yokes in television sets, receptacles, sockets,sockets for Christmas lamps, CRT monitor bodies, blow outlet blades ofair conditioner apparatuses, blow direction selectors, humidifiercovers, microwave oven doors, toilet seats of a washing toilet seats“Washlet”, tanks for hot water, motor covers and control panels forelectric fans, connectors, PPC toner containers, and ventilating fancovers;

-   -   civil engineering and construction-related products such as        troughs and rids, electric wire covers and pipes for underground        utilities, pipe covers, mono-filaments and laminate film for        flat yarn, chairs for stadium use and their back board covers,        flower pots for foliage plants, members of floor adapted to        office automation, and wall paper sheets;    -   automobile parts such as corrugated tubes and pipes for electric        wire, floor mats, members of door trim, trunk room sheets and        linings, battery casings, radiator cooling fans, fall-preventing        panels for an engine room, instrument panels, members of        interior trim, glove boxes, console boxes, fan shrouds, air        cleaner housings, sheet frames, connectors, and ashtrays; and        miscellaneous goods such as polypropylene bands, containers, and        pallets.

EXAMPLES

The present invention will next be described in detail by way ofExamples and Comparative Example, which should not be construed aslimiting the invention thereto.

Example 1

Diethylene glycol (4.32 g), ε-caprolactone monomer (395.8 g), amono-n-butyltin fatty acid salt (0.06 g), Epikote 828 (bisphenol A epoxyresin, product of Yuka Shell Epoxy (epoxy eq. 187, liquid form at 25°C.)) (0.8 g) serving as a hydrolysis inhibitor, and potassiumperfluorobutylsulfonate (product name: RM-65, product of Miteni) (400 g)were placed in a separable flask. Under nitrogen flow, the mixture washeated with gentle stirring to 170° C., and allowed to react at thetemperature for six hours. Thereafter, the reaction mixture was removed.The mixture was found to assume a uniform waxy substance. Then, themixture was added to polycarbonate resin (product name: Panlite L-1225Y,product of Teijin Chemicals Ltd.) such that the RM-65 content wascontrolled to 0.1 parts by weight based on 100 parts by weight of thepolycarbonate resin. The resultant mixture was mixed by use of atumbler, and molded by means of an injection molding apparatus, therebyproducing two types of molded articles having dimensions: 12.5 mm(width)×125 mm (length)×3.2 mm (⅛ inch) or 2.5 mm ({fraction (1/10)}inch) (thickness). The molded article pieces were subjected to aflammability test on the basis of the UL94 standards. The flammabilitytest results were evaluated on the basis of the presence or absence ofignition of test pieces. Furthermore, a part of molded articles wereplaced in an oven (at 40° C.) for one month, and the surface wasobserved after the storage so as to check blooming.

Example 2

As the polyester resin (B), polycaprolactone resin (product name:Placcel H1P (number average molecular weight: about 10,000), product ofDaicel Chem. Ind. Ltd.) (200 g) was placed in a separable flask andheated to 130° C. under nitrogen flow, thereby melting the resin. Theaforementioned potassium perfluorobutylsulfonate (100 g), serving as thefluorine compound (A), was added to the molten resin. The mixture washeated to 170 and stirred for about one hour and 30 minutes, whereby ahomogeneous solution was formed. In a manner similar to that employed inExample 1, the thus-produced solution was added to polycarbonate resin,molded articles were produced from the resin mixture, and a flammabilitytest was performed.

Example 3

The procedure of Example 2 was repeated, except that the aforementionedpolycaprolactone resin was used in an amount of 200 g and theaforementioned potassium perfluorobutylsulfonate in an amount of 200 g,to thereby produce test specimens. The test was performed in a mannersimilar to that of Example 1.

Comparative Example 1

The procedure of Example 1 was repeated, except that the aforementionedpotassium perfluorobutylsulfonate (0.1 parts) was added to polycarbonateresin, to thereby produce test pieces and perform the flammability test.

Table 1 shows the flammability test results of Examples 1 to 3 andComparative Example 1. In Table 1, fluorine compound (A) content andpolyester resin (B) content (parts by weight) are on the basis of 100parts by weight of the resin to which the flame retardant compositionhas been added. TABLE 1 Ex. 1 Ex. 2 Ex. 3 Polymeriza- PreliminaryPreliminary Comp. tion mixing mixing Ex. 1 Fluorine compound 0.10 0.100.10 0.10 (A) RM65 content Polyester resin (B) 0.10 0.20 0.10 — content⅛ Non-drip 5 5 4 3 inch Drip, no 0 0 1 0 flaming Drip, 0 0 0 2 flaming{fraction (1/10)} Non-drip 3 4 0 0 inch Drip, no 1 0 1 0 flaming Drip, 11 4 5 flaming Blooming no no no yes

As is clear from Table 1, flame retardant resin compositions containingpolycaprolactone resin (product name: Placcel H1P), a type of polyesterresin (B), exhibit more excellent flame retardant characteristics ascompared with the flame retardant resin composition of ComparativeExample 1 employing only a conventional flame retardant. In addition,each polycarbonate resin composition to which the flame retardantcomposition of Example 1, 2, or 3 has been added causes no bleeding ofthe flame retardant for a long period of time. In contrast, slightblooming attributed to bleeding out was observed on the surface ofmolded articles of the polycarbonate composition of Comparative Example1, after one month storage at 40° C. of the molded articles.

Industrial Applicability

According to the present invention, there can be provided a flameretardant composition which can provide flame retardant effect throughaddition of the composition in a very small amount, exhibits gooddispersibility, and provides molded articles containing a flameretardant not causing bleeding. A flame retardant resin compositioncontaining the flame retardant composition can also be provided.

1. A flame retardant composition, characterized in that the compositioncomprises, as essential ingredients, a fluorine compound (A) representedby the following formulaR¹—SO₂—R² or R¹—SO₃ ⁻M⁺  (1) (wherein R¹ represents a C₁-C₁₂perfluoroalkyl group, a C₂-C₈ perfluoroalkenyl group, a C₆-C₁₂perfluoroaryl group which may be substituted, a C₃-C₁₂perfluoroalicyclic hydrocarbon group, or a C₇-C₁₂ perfluoroaralkylgroup; R² represents a halogen atom, an N-alkylamino group, or anN-alkyl-N-hydroxyalkylamino group; and M represents an alkali metal) anda polyester resin (B).
 2. A flame retardant composition as claimed inclaim 1, wherein the composition contains the fluorine compound (A) inan amount of 0.1 parts by weight to 90 parts by weight and the polyesterresin (B) in an amount of 10 parts to 99.9 parts by weight, the totalamount of (A) and (B) being 100 parts by weight.
 3. A flame retardantcomposition as claimed in claim 1 or 2, wherein the fluorine compound(A) is at least one species selected from among potassiumperfluorobutylsulfonate, potassium perfluorooctylsulfonate, lithiumperfluorooctylsulfonate, potassium perfluoro-4-ethylcyclohexylsulfonate,perfluorobutanesulfonyl fluoride, perfluorohexanesulfonyl fluoride,perfluorooctanesulfonyl fluoride, N-ethylperfluorooctanesulfonamide, andN-ethyl-N-hydroxyethylperfluorooctanesulfonamide.
 4. A flame retardantcomposition as claimed in any one of claims 1 to 3, wherein thepolyester resin (B) is a lactone polymer.
 5. A flame retardantcomposition as claimed in claim 4, wherein the lactone polymer isobtained from at least one species of ε-caprolactone,trimethyl-ε-caprolactone, monomethyl-ε-caprolactone, γ-butyrolactone,and δ-valerolactone through ring-opening polymerization in the presenceof a compound having at least one active hydrogen atom.
 6. A process forproducing a flame retardant composition, characterized in that theprocess comprises polymerizing a lactone monomer in the presence of afluorine compound (A) represented by the following formula (1):R¹—SO₂—R² or R¹—SO₃ ⁻M⁺  (1) (wherein R¹ represents a C₁-C₁₂perfluoroalkyl group, a C₂-C₈ perfluoroalkenyl group, a C₆-C₁₂perfluoroaryl group which may be substituted, a C₃-C₁₂perfluoroalicyclic hydrocarbon group, or a C₇-C₁₂ perfluoroaralkylgroup; R² represents a halogen atom, an N-alkylamino group, or anN-alkyl-N-hydroxyalkylamino group; and M represents an alkali metal). 7.A flame retardant resin composition comprising a flame retardantcomposition as claimed in any one of claims 1 to 5 and a thermoplasticresin or thermosetting resin.
 8. A flame retardant resin composition asclaimed in claim 7, wherein the resin composition contains the fluorinecompound (A) in an amount of 1% by weight or less.
 9. A flame retardantresin composition as claimed in claim 7, wherein the resin compositioncontains the polyester resin (B) in an amount of 1% by weight or less.10. A molded article produced by molding a flame retardant resincomposition as claimed in any one of claims 7 to 9.